Packaging machine

ABSTRACT

A packaging machine comprises a transfer device for inserting a product into a package and a circulating leaflet supply device comprising a plurality of tong-like holders which are disposed in a row, for receiving one leaflet each, and for bringing the leaflet into the region of the transfer device between the product and the package such that it can be inserted together with the product into the package. An opening unit with at least one stop is disposed in the transport path of the holders for opening the holders to release the leaflet. The stop can be adjusted in dependence on an opening signal of a control device between an operative position opening the holders and an inoperative position in which the holders pass the stop without releasing the leaflet. A first detector device is thereby provided for detecting the insertion motion of the product into the package and for transmitting a corresponding insertion signal to the control device when the product is being inserted, wherein the control device generates the opening signal only when the insertion signal is present.

[0001] The invention concerns a packaging machine comprising a transferdevice for inserting a product into a package, and with a circulatingleaflet supply device comprising a plurality of tong-like holders whichare disposed in a row, for receiving one leaflet each, the leafletsupply device disposing the leaflet, in the region of the transferdevice, between the product and the package, such that the leaflet canbe inserted together with the product into the package, wherein anopening unit comprising at least one stop is disposed in the transportpath of the holders by means of which the holders can be opened forreleasing the leaflet, wherein the stop can be adjusted in dependence onan opening signal of a control device between an operative positionwhich opens the holder and a non-operative position in which the holderpasses the stop without releasing the leaflet.

[0002] A packaging machine of this type usually has a first circulatingsupply device for the package, e.g. a so-called folded box chain, and asecond circulating supply device for the products, e.g. a so-calledproduct chain. The motions of these two chains are synchronized suchthat the product can be inserted by an insertion plunger, transverselyto the direction of motion of the chains, laterally into the folded box.For certain products, e.g. medication, an additional leaflet or sidenote must be inserted into the package. For this reason, one furthercirculating supply device is provided in the form of a so-called leaflettong chain which supports several tong-like holders which each canreceive and clamp one leaflet. A leaflet to be inserted into the packageis moved between the product and the folded box by the leaflet tongchain and is carried along by the product through its lateral insertingmotion to be inserted into the folded box. As soon as the product abutsthe leaflet, the tong-like holder must be opened to release the leaflet.Towards this end, an opening unit is provided in the region of thetransfer device, e.g. in the form of a stop or opening wedge, againstwhich the tong-like holder abuts during its supply motion therebyopening the tong arms and releasing the leaflet.

[0003] During operation of the packaging machine, small irregularitiesare likely to occur, whereby the folded boxes are possibly supplied tothe folded box chain or the products are supplied to the product chainin a discontinuous fashion such that either one or more sections of thefolded box chain have no folded box or one or more sections of theproduct chain contain no product. A sensor detects when a folded box ora product is missing whereupon no product is inserted or the insertionplunger is not activated.

[0004] In older packaging machines, the opening wedge is rigidlyinstalled in consequence of which the tong-like holder also opens whenno product is being inserted into a folded box. It has turned out thatthe leaflet released in this case, can move randomly through thepackaging machine and cause malfunction of the packaging machine as wellas temporary stoppage, which requires time-consuming and expensivemanual intervention. To solve this problem, DE 199 18 527 A1 proposes tobring the opening wedge out of the transport path of the tong-likeholder into an inoperative position when required. In this fashion, thetong-like holder opens and releases the leaflet only when a folded boxis actually present in the folded box chain and the product chaincontains a product. When no folded box or no product is present, theopening wedge is removed from the transport path of the tong-like holdersuch that the tong-like holder with leaflet passes the opening wedge andis not opened thereby. The opening wedge then returns into its operativeposition to open the following tong-like holder if the conditionsrequired therefor are met.

[0005] The cycling times provided in a modern packaging machine for oneworking cycle are only a few milliseconds. During this time, theconditions required for adjusting the opening wedge, at least withregard to the product and the package, must be detected and evaluatedand the operating means must be activated to adjust the stop. Theplunger inserting the product into the package is activated only when aproduct is present, when a leaflet is present which has the correctcode, and when a package or folded box is present. The correspondinginquiries or detections are carried out in the packaging machine and thecorresponding data is stored in a so-called shift register and can bequeried therefrom. This data also forms the basis for the decisionwhether the tong-like holder is opened to release the leaflet or remainsclosed.

[0006] The packaging machine stores one data set for each package unit,comprising the product, the folded box and the leaflet, wherein the dataset contains all essential conditions and control data of the packageunit. Since a plurality of package units are processed simultaneouslyand pass through the packaging machine, the data sets are conventionallystored in a common data storage. The data storage is a shift registerand the data sets within that shift register are shifted, i.e.displaced, within the shift register in time steps corresponding to theworking cycle of the machine, i.e. to the changing position of theassociated package unit in the packaging machine continuing up to theejector station. The shift register is timed via a shift frequencystrobe which is usually extracted from the product chain drive.

[0007] A packaging machine must be able to process products and packagesof different formats and also different leaflet formats. The individualcomponents of the transfer station of the packaging machine must beadjusted relative to each other in dependence on the product sizes, thepackage sizes and the leaflet sizes. The leaflet tong chain with thewedge opening the tongs, is usually adjusted relative to the productchain and/or the folded box chain when the format is changed. Inconsequence thereof, the point in time when the opening wedge isoptionally brought from its inoperative position into its operativeposition (opening wedge time) is also adjusted relative to the shifttiming of the shift register, which defines the start of a processingcycle of the packaging machine. Due to adjustment of the opening wedgetime relative to the shift timing of the shift register, a situation maybe created in which the two points in time coincide or are at leastsufficiently close to each other that the control does not detect andprocess them as two independent signals. This situation can produceincompatible developments in the control and inadmissible operatingstates which can lead to stoppage of the packaging machine in responseto malfunction. To eliminate the disturbance, the mechanical andelectronic settings of the packaging machine and, in particular, of theleaflet tong chain relative to the product chain must be changed untilsafe operation is ensured. Such adjustment is possible since there is acertain time tolerance during transfer of the leaflet from the tong-likeholder of the leaflet tong chain. Nevertheless, elimination of thedisturbance is demanding and has a negative influence on the overallperformance of the packaging machine.

[0008] It is the underlying purpose of the present invention to providea method for controlling a packaging machine of the above-mentionedtype, wherein adjustment of the stop or opening wedge relative to theproduct chain and/or the folded box chain produces no conflict betweenthe shift time of the shift register and the opening wedge time.

[0009] This object is achieved in accordance with the invention with apackaging machine having the characterizing features of claim 1.

[0010] The invention is based on the principal idea that initiation ofthe opening motion of the tong-like holder is not directly based on theabove-mentioned data of the shift register, rather indirectly, in that afirst detector device detects the insertion motion of the product intothe package and emits a corresponding insertion signal to the controldevice when the product is inserted. The control device generates anopening signal only when an insertion signal is present, i.e. when theproduct has actually been inserted, in response to which, the openingwedge is brought into its operative position in which it opens thetong-like holder.

[0011] An insertion motion of the product occurs only when the insertionplunger is initiated, which, in turn, depends on satisfying theabove-mentioned conditions (leaflet present? Product present? Folded boxpresent? Leaflet code correct?). When the first detector devicedetermines that the insertion plunger is moved or the product isinserted, the above-mentioned conditions must all be met. The insertionsignal then indicates whether or not the leaflet is to be releasedthrough opening the associated tong-like holder.

[0012] The first detector device can directly detect the insertionmotion of the product. Alternatively, it is also possible that the firstdetector device detects the insertion motion of the insertion plungerabutting the product.

[0013] In a preferred embodiment of the invention, the first detectordevice comprises a first initiator, which can be initiated by anypassing insertion plunger, and a second initiator which can be initiatedonly by an insertion plunger inserting the product. This embodiment isfavourable in terms of control. The first initiator is preferablydisposed upstream of the second initiator with respect to the transportdirection and is crossed and triggered by every insertion plunger i.e.independently of whether the insertion plunger actually carries out aninsertion motion to insert the product or if the insertion motion issuppressed through disablement of the insertion plunger. The insertionplunger crossing the first initiator resets an intermediate storage ormark to a value 0. When the insertion plunger subsequently starts aninsertion motion of the product, it crosses the second initiator andtriggers it thereby setting the intermediate storage to the value 1.Only when the intermediate storage has the value 1 is an insertionsignal transmitted to the control device. The next insertion plungerresets the intermediate storage to 0 when the first initiator istriggered.

[0014] In a preferred embodiment of the invention, the initiators can betriggered by the insertion plunger without contact, which is the case,in particular, when the initiators are metal detectors, magneticswitches or light barriers which are triggered or switched by theinsertion plunger.

[0015] In a preferred embodiment of the invention, the first detectordevice and the opening unit can be adjusted together as a unit in thetransport direction of the leaflet supply device. Towards this end, theabove-mentioned components are disposed on a common adjustable frame.This embodiment is advantageous in that adjustment of the opening unitfor changing the format, e.g. when the product size is changed,simultaneously also displaces the first detector device with the twoabove-mentioned initiators by the same amount and the temporalassociation between the first detector device and the opening unit ismaintained.

[0016] A further development of the invention may have an additionalsecond detector device for detecting the position of the next holder tobe opened and transmitting a corresponding holder signal to the controldevice. The second detector device determines that a holder has reacheda predetermined position. The control device also evaluates whether thetong-like holder is to be opened or shall remain closed due to thereceived insertion signal and whether the holder to be opened isproperly aligned. When both conditions are met, the stop or the openingwedge can be brought or held in the operative position throughtriggering of an actuating device to open the holder as determined bythe second detector device. When the actuating device of the openingwedge is not activated, the tong-like holder passes the opening unit orthe opening wedge without being opened. The leaflet is then removed fromthe holder and discharged or dispatched in a suitable manner at anotherposition of the leaflet supply device, e.g. by means of a further stop.

[0017] When the format is changed, the second detector device isadjusted in the transport direction of the leaflet supply device,preferably as a unit together with the first detector device and theopening unit. In this fashion, the spatial and therefore temporalrelationship among the components is also maintained after displacement.

[0018] In a further development of the invention, the stop ispretensioned by a spring into its inoperative position such that thecontrollable actuating device must be activated against the springpretension to bring or keep the stop in the operative position when theconditions required for opening the tong-like holder and releasing theleaflet are met. The actuating device may be a pneumatic or hydraulicadjustment cylinder. In particular, the stop or the opening wedge can beadjusted, preferably displaced, substantially perpendicular to thetransport supply device.

[0019] Further details and features of the invention can be extractedfrom the following description of an embodiment with reference to thedrawing.

[0020] The single FIGURE shows a schematic representation of a transferdevice in a packaging machine.

[0021] The FIGURE schematically shows a transfer device 10 of apackaging machine which comprises a folded box chain 28 (onlyschematically shown) extending in the direction of the arrow FK forreceiving folded boxes or packages V, and a product chain 29 extendingparallel thereto in the direction of the arrow PK with products P to bepackaged. To simplify the illustration, the FIGURE shows only onepackage V and one product P. The motions of the folded box chain 28 andthe product chain 29 are synchronized such that the product P can beinserted into the open package V via an insertion plunger 11 of thetransfer device 10 acting transverse to the direction of motion of thechains 28 and 29. The insertion plunger 11 thereby follows an insertioncurve EK.

[0022] A circulating leaflet tong chain 27 (transport path PZK) extendsbetween (below and parallel to) the folded box chain 28 and the productchain 29, and carries a plurality of tong-like holders 15, 16 at regularintervals between the jaws of which one leaflet (not shown) can beclamped with upright alignment. The leaflet is guided such that it ispositioned between the package V and the product in the region of thetransfer device 10. When the product P is transversely inserted into thepackage V, the leaflet is carried along thereby and inserted into thepackage V. When the leaflet is inserted into the package V, the holder15, 16 which clamps the leaflet must be opened. Towards this end, thetransfer device 10 has an opening unit 12. The opening unit comprises anadjustable stop or opening wedge 13 which extends parallel to thetransport path PZK of the leaflet tong chain 27 or the tong-like holders15, 16. The opening wedge 13 has an associated actuating device 24 bymeans of which the opening wedge 13 can be adjusted substantiallyperpendicularly to the transport path PZK of the tong-like holders 15,16 between an operative position and a withdrawn, inoperative position.The opening wedge 13 is thereby pretensioned into its inoperativeposition by a spring (not shown).

[0023] The tong-like holders 15, 16 disposed on the leaflet tong chain27 conventionally have clamping jaws or tongs for clamping the leaflet.Each holder moreover has an axis extending transverse to the transportpath PZK on which rollers 17 or 18 are rotatably disposed to form a stoppart of the holder 15 or 16. The stop part with rollers 17 or 18 isoriented such that the latter abut the opening wedge 13 when it is inits operative position.

[0024] The FIGURE shows that the insertion plunger 11 has an associatedfirst detector device 19 for detecting whether the insertion plunger isdisplaced to insert the product P. The first detector device 19comprises a first initiator 19 a which is triggered by each passinginsertion plunger 11 and a second initiator 19 b disposed behind thefirst initiator 19 a in the transport direction PZK which is onlytriggered by an insertion plunger 11 which inserts the product P. Thefirst initiator 19 a resets an intermediate storage or mark to the value0 as soon as an insertion plunger 11 passes or crosses it. When theinsertion plunger 11 follows the insertion curve EK via points set bythe shift register to thereby insert the product P, it also passes thesecond initiator 19 b as a result of which, the intermediate storage ormark is set to the value 1. The first detector device 19 with the twoinitiators 19 a and 19 b is disposed on a plate 14 which is structurallyconnected to the opening unit 12. When the intermediate storage has thevalue 1, the first detector device 19 transmits a correspondinginsertion signal to the control device 26 via a data line L.

[0025] Moreover, a second detector device 20 is provided close to theleaflet tong chain 27 in front of the opening unit 12, for detectingthat the next tong-like holder to be opened has reached a predeterminedposition. The second detector device 20 transmits a corresponding holdersignal to the control device 26 and the signals are processed in thecontrol device 26. When the first detector device 19 has determined thatthe product P has been inserted and when the second detector device 20determines that the next holder has reached its desired position, allrequired conditions for releasing the leaflet from the tong-like holder15 or 16 are met. The control device 26 controls the actuating means 24of the opening wedge 13 such that it is brought into its operativeposition. The holder 15 abuts against the opening wedge 13 and is openedto release the leaflet which is then carried along by the product Pduring its insertion motion and is inserted into the package V.

[0026] When the first detector device 19 determines that the product Pis not inserted, all conditions which are required for correct transferof the product P are not met. The second initiator 19 b is not triggeredand does not set the intermediate storage to the value 1 and noinsertion signal is generated for the control device 26. The controldevice 26 detects that the opening wedge for the next tong-like holdershould be brought into the inoperative position to ensure that theholder does not abut the opening wedge and is accordingly not opened.The leaflet remains in the tong-like holder and is removed and divertedat another point of the leaflet tong chain.

[0027] When the packaging machine is adjusted to another product format,the first detector device 19, the second detector device 20, and theopening unit 12 are commonly adjusted as a unit in the transportdirection PZK of the transport supply device 27, while maintaining theirmutual relative locations and orientations.

1. Packaging machine comprising a transfer device for inserting aproduct (P) into a package (V) and with a circulating leaflet supplydevice (27) comprising a plurality of tong-like holders (15, 16) whichare disposed in a row, for receiving one leaflet each, and for bringingthe leaflet into the region of the transfer device between the product(P) and the package (V), such that it can be inserted together with theproduct (P) into the package (V), wherein an opening unit (12) isdisposed in the transport path of the holders (15, 16) having at leastone stop (13) for opening the holders (15, 16) to release the leaflet,wherein the stop (13) can be adjusted in dependence on an opening signalof a control device (26) between an operative position opening theholders (15, 16) and an inoperative position in which the holders (15,16) pass the stop (13) without releasing the leaflet, characterized inthat a first detector device (19) is provided which detects theinsertion motion of the product (P) into the package (V) and transmits acorresponding insertion signal to the control device (26) when theproduct (P) is being inserted, wherein the control device (26) generatesan opening signal only when the insertion signal is present. 2.Packaging machine according to claim 1, characterized in that the firstdetector device (19) detects the insertion motion of an insertionplunger (11) abutting the product (P).
 3. Packaging machine according toclaim 1 or 2, characterized in that the first detector device (19)comprises a first initiator (19 a) which can be triggered by eachpassing insertion plunger (11), and a second initiator (19 b) which canbe triggered only by an insertion plunger (11) inserting the product(P).
 4. Packaging machine according to claim 3, characterized in thatthe first initiator (19 a) resets an intermediate storage to the value 0and the second initiator (19 b), which is disposed downstream of thefirst initiator (19 a) with respect to the transport direction, sets theintermediate storage to the value 1 when triggered, wherein theinsertion signal is transmitted to the control device (16) only when theintermediate storage has the value
 1. 5. Packaging machine according toclaim 3 or 4, characterized in that the initiators (19 a, 19 b) can betriggered by the insertion plunger (11) without contact.
 6. Packagingmachine according to claim 5, characterized in that the initiators (19a, 19 b) are formed by metal detectors, magnetic switches or lightbarriers.
 7. Packaging machine according to any one of the claims 1through 6, characterized in that the first detector device (19) and theopening unit (12) are adjustable as a unit in the transport direction(PZK) of the leaflet supply device (27).
 8. Packaging machine accordingto any one of the claims 1 through 7, characterized by a second detectordevice (20) which detects the position of the next holder (15, 16) to beopened and transmits a corresponding holder signal to the control device(26).
 9. Packaging machine according to claim 8, characterized in thatthe stop (13) can be brought into the operative position in dependenceon the insertion signal and the holder signal.
 10. Packaging machineaccording to claim 8 or 9, characterized in that the second detectordevice (20) can be adjusted, as a unit together with the first detectordevice (19) and the opening unit (12) in the transport direction (PZK)of the leaflet supply device (27).
 11. Packaging machine according toany one of the claims 1 through 10, characterized in that the stop (13)is pretensioned by a spring into its inoperative position and the stop(13) has an associated controllable actuating device (24) with which thestop (13) can be brought into the operative position in opposition tothe spring pretension.